This invention relates generally to process monitoring systems, and, more particularly to a high resolution, high accuracy monitoring system capable of 3D process monitoring with 2D video and a precise angular aiming system.
Manufacturing errors are expensive. An error in manufacturing results in costs relating to raw materials, machine time, resolution time, and rework or scrap disposal.
The cost of a manufacturing error is lowest when the error is detected and corrected at the earliest possible time in the process. Each process which occurs after a manufacturing error has occurred adds costs to the product. The flawed product will eventually cause a manufacturing disruption or become scrap. A dimensioning error which is not detected when the dimension is created can allow the repeated production of parts which will not function properly.
It has been said that quality cannot be "inspected into" parts. Quality is the result of each and every process occurring correctly. By monitoring dimensional quality "in process" (as the process is occurring) problems can be detected and resolved at the earliest possible time and at the lowest possible cost. The detection of developing problems, during process deterioration but before unacceptable processing occurs, lowers costs and improves the efficiency of a manufacturing system. Costs are reduced by resolving the problem before scrap is created or downstream disruptions occur.
A single fixed camera has a resolution which generally does not exceed 640 by 480 pixels. Single camera inspection has been limited to 2D inspection of small areas (tens of square feet). Large inspection fields are supported by mounting the camera on a gantry. The gantry is generally 2D, and the cost and complexity associated with precision over large areas rapidly becomes prohibitive.
Another method of expanding the field size of a single camera is to aim the camera through a pair of XY galvanometric mirrors. While this increases the field size for the single camera, accuracy and precise focus are limited. Inspection cameras aimed through mirrors are limited to 2D applications.
Another drawback of single camera systems (stand alone, on gantries or aimed with mirrors) is the complexity and unreliability of the video processing task for the data read in from the camera.
It is therefore an object of this invention to provide 3D process monitoring with a 2D video system.
It is a further object of this invention to position a camera's viewing field in small regions of interest which may be occur anywhere over a large area.
It is still a further object of this invention to control inspection parameters in processing the data captured by a video camera.
It is another object of this invention to generate 2D views of 3D characteristics for the purpose of limiting regions of interest in a video camera inspection system.